A door latch assembly is provided with enhanced acoustic dampening characteristics, and includes a door bolt assembly having an inside barrel and an outside barrel configured for accommodating reciprocal sliding action of the inside barrel between a latch position and a release position. At least one barrel acoustic isolator is associated with at least one of the inside barrel and the outside barrel, and is configured for dampening sound generated by the reciprocal action.

An electric latch retraction device for vertical rod door latches includes an automatic adjustment feature including a limit switch and a linear sensor, such as a Hall effect sensor, which detects vertical position. A microcontroller monitors the vertical position of a pivoting retraction lever driven at the pivot by a linear driver. The housing for the electric latch retraction device is preferably external to the door and one end of the retraction lever extends into the door to drive a vertical rod door latch mechanism while an opposed end contacts the limit switch to signal that continued driving of the linear driver will begin to drive the vertical rod door latch. The microcontroller determines from the vertical position of the retraction lever when the limit switch is actuated whether the electric latch retraction device is mounted too high or too low.

An improved door lock mechanism is a door locking device having heavy plates that sandwich the door frame above or below the door knob of a door with bolts passing through the plates to secure it to the door frame, and a barrel lock accessible through the outside plate with a barrel key. The locking mechanism is attached to a locking bar on the inside that is attached to a lock shaft rotatable on the door frame side which rotates downward into a slot formed in a plate that is attached to the inside of the door adjacent the frame plates. Together the frame plates, the door plate, and the rotating bar function as a door bar.

An improved door lock mechanism is a door locking device having heavy plates that sandwich the door frame above or below the door knob of a door with bolts passing through the plates to secure it to the door frame, and a barrel lock accessible through the outside plate with a barrel key. The locking mechanism is attached to a locking bar on the inside that is attached to a lock shaft rotatable on the door frame side which rotates downward into a slot formed in a plate that is attached to the inside of the door adjacent the frame plates. Together the frame plates, the door plate, and the rotating bar function as a door bar.

A magnetic self-latching device for a gate has a main body with handles on either side for operation or has an arrangement to be remotely actuated. A latching body has a high strength magnet usually provided at the bottom of a cavity which defines a latching shoulder. The latching body is adapted to be fixed to a gate post. The main body, with its housing, can be mounted on the gate frame and incorporates a latch pin which, in the door-closed position, is displaced by magnetic attraction to an extended latching position and against the biasing of a return spring. The gate cannot be opened until actuation of the mechanism occurs, for example by rotating a handle to retract the pin against the magnetic force; the gate can then be swung open. When the handle is released, the biasing spring retains the latch pin in a retracted position.

A magnetic self-latching device for a gate has a main body with handles on either side for operation or has an arrangement to be remotely actuated. A latching body has a high strength magnet usually provided at the bottom of a cavity which defines a latching shoulder. The latching body is adapted to be fixed to a gate post. The main body, with its housing, can be mounted on the gate frame and incorporates a latch pin which, in the door-closed position, is displaced by magnetic attraction to an extended latching position and against the biasing of a return spring. The gate cannot be opened until actuation of the mechanism occurs, for example by rotating a handle to retract the pin against the magnetic force; the gate can then be swung open. When the handle is released, the biasing spring retains the latch pin in a retracted position.

Disclosed are various embodiments of lock devices, systems, and methods. A lock of the application can include an internal mechanism to permit backdriven operation and lost motion operation. In one form the lock can be made from an assembly of parts that have locating features that require one way installation/assembly. The lock can include an internal power source capable of driving electronics used to determine handedness of a door.

A lock device with an electric locking function includes a latch head slideably mounted in a case and an unlatching mechanism mounted in the case. The unlatching mechanism includes a follower portion operatively connected to the latch head. The unlatching mechanism further includes a locking mechanism having an electric driving device for driving a locking block to move between a front position in which the unlatching mechanism is locked and a rear position in which the unlatching mechanism is not locked. Wire or wireless control can be provided to control a driving shaft of the electric driving device to move in a forward direction or a reverse direction to lock or unlock the latch head.

A door lock mounted to a door includes a latch head. A receiver includes a charging circuit and is mounted to the door. A battery provides electricity required for moving the latch head between a latching position and an unlatching position or providing electricity required for permitting or not permitting movement of the latch head from the latching position to the unlatching position. A transmitter includes a wireless transmitting circuit and is mounted to a door frame to which the door is pivotably mounted. The transmitter is connected to a power supply. When the door is in an open position, the receiver is not aligned with the transmitter. When the door is in a closed position, the receiver is aligned with the transmitter, the receiver receives a radio wave from the transmitter, converts the radio wave into electricity, and stores the electricity in the battery.

A handle for a compartment of a low, medium or high voltage switchgear includes: a body part; a hand grasping part; and a lock. The handle is movable from a closed position to an open position. When the handle is in the closed position, the handle is not useable to open a door of a compartment of the switchgear. When the handle is in the open position, the handle is useable to open the door of the compartment of the switchgear. In the open position, the hand grasping part is positioned so as to be graspable by a human user. In the closed position, a transition of an active element in the compartment of the switchgear from a quiescent state to an active or potentially active state activates the lock. Activation of the lock stops the handle from moving from the closed position to the open position.